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R aspberry

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avoids infestation. Monitoring for SWD was only done in the general area during this trial so specific cultivar infestation is unknown. Cultivar preference studies have had mixed results as far as infestation rates in specific cultivars (Burrack et al., 2012; Lee et al., 2011) but high rates of infestation have gen- erally been observed in raspberries. In order to reduce the impact of this pest, a diligent monitoring program should be followed, es- pecially late in the season, to identity any fly infestation and to implement an appropriate insecticide program if needed, rotating rec- ommended chemical classes (Pritts et al., 2015) if needed. Alternatively, complete ex- clusion with netting (http://blogs.cornell.edu/ swd1/2016/04/19/exclusion-netting-against- swd/) could be used to control the insect, but this may not be cost effective unless earlier infestation dates are observed in the future.  While a direct comparison to open field production was not done in this trial, many of the cultivars had improved fruit size com- pared to previous open field trials (Weber et al., 2004a, 2004b, 2005). However, some displayed characteristics that may limit their suitability for production under tunnels or for marketing. The canes of ‘Killarney’ grew in a very curvy, uncontrolled manner and were less upright than observed in outdoor trials, making them difficult to prune and train. The fruit of ‘Killarney’ was also darker red, espe- cially after storage, than is generally desirable for fresh raspberries but may be acceptable for local markets. This cultivar is typically darker red, but the color intensity may have been affected by the higher temperatures ex- perienced in the high tunnels. ‘Moutere’ had very attractive fruit with good firmness and uniformity, but the flavor was very poor and generally unacceptable for fresh consump- tion. This could possibly be attributed to the conditions under the high tunnels but is more likely a regular characteristic of this cultivar (H. Hall, pers. comm.). ‘Titan’ displayed the same susceptibility to Phytophthora root rot observed in open field conditions (Maloney et al., 1993). The noticeable drop off in vigor

2018). The flowering period of floricane cultivars is much more concentrated than primocane cultivars since the whole plant is emerging from dormancy simultaneously so that the fruiting laterals form much more uniformly than in primocane cultivars where new laterals are produced progressively down the cane for many weeks. This flower- ing pattern makes for a much more concen- trated harvest in floricane cultivars.  The late cultivars in this trial stretched the season to late July or early Aug. in each year (Table 3). There is at least one cultivar, ‘Oc- tavia’ (Solomon, 2013), not included in this trial that continues to fruit beyond the win- dow of K81-6 and ‘Encore’ but it seems that breeders are nearing the limits of what can be accomplished through genetics to lengthen the floricane season. However, by combining optimal production practices with late flori- cane and early primocane fruiting cultivars, continuous production of red raspberries for up to 6 months in cool climate locations such as western NY is possible. The development of improved cultivars is needed to take ad- vantage of this long window, especially large fruited cultivars for the early season and firmer cultivars overall.  While the overall yield performance of the floricane cultivars under high tunnels was similar to what has been recorded in outdoor trials in NY (Weber et al., 2004a; 2004b; 2005), the trial in Michigan showed consid- erable yield advantage (Hanson et al., 2011). Additionally, fruit quality aspects of the fruit in this trial, especially size, were consider- able so that the advantages of high tunnel production when optimized likely justify the increase input costs. Pest control require- ments in this trial were significantly reduced compared to outdoor trials with no fungi- cides applied and only minimal hand weed- ing. Even without fungicide treatments, no appreciable fruit rots were observed. In most years, spotted winged drosophila (SWD) ( Drosophila suzukii ) does not become a pest problem in the region until late July to early Aug. so that most of the floricane production